Process for stabilising esters of acids of phosphorus and stable compositions of esters of acids of phosphorus



PROCESS FOR STABILISING oF' Acrns or PHOSPHORUS AND STABLE COMPOSITIONS OF OF ACIDS OF PHOSPHQRUS' I I Hans Diriwiichter, Oftring en, Switzerland, also, to 'J.

R. Geigy A.-G., Basel, Switzerland H 7 K The present invention concerns a proces's forthe stabilising of. phosphoric acid estersf 'which can hefused, I

for :example, in the production'of pesticides. 1

Surprisingly it "has .now been found that 'phosphoric acidesters-can be stabilised byfadding compounds-which contain an epoxide groupto such esters of preparations o'ctyl or iso-octyl-phenofwith 5'-10 molsof ethylene 45 parts of xylene r is stored for 240 days at 50 As the end of this time, the content of thiophosphoric acid-[2-isopropyl-4- 'methyl-pyrimidyl-(6) l-diethyl ester has sunk to 10 parts;

Under the same storing conditions, ananalogous composition in which: 1 part of xylene has been replaced by 1 part 0t epichlorohydrin, remains j stable, i. e.- there is no loss; oflcontent of the thiophosphoric acid, ester named.

Example 2 of ins'ecticidal active ingredient, consisting 0t 7 60 parts of thiophosphor ic acid-l2-isopropyl-4 methylpyrimidyl-loll-diethylgester 33 m an amp phenol-ethylene saac condensation i p'roduct condensationfproduct of Iniolof'nonyL,

as well as;from' any other type of decompositionis meant 4 1 by stabilisation. Compounds having an'epoxide group,

which are suitable-stabilising agentsaare,intiarticdlar,

In this invention, esters of all acids of pentavalent and 7 also trivalent phosphorus are meant by phosphoric ;acid

esters, thus, for example, apart from the esters of ""rtho phosphoric acid alsothose. ot1pyro&,ftrif and ltetra'phos phoric acid, thiophosphor'ic acid, dithiophosphorieacid,

epichlorohydrin,eyclohexene oxide,propyl ene oxide andor iso oct' f-phenol with 5-{10' mols of ethylene thereoffi In this connection, protection tromhydrolysis; jpansofiylen ,5 j"

the} content. of thiophosphoric :acid-[2-isopropyl-4- V methyl-pyrimidyl;@llfdiethyl ester has sunk to 20 parts whereas in this case also,- thecontent: of the thiophosphorie acid ester named remainsunchanged when can analogous composition containing 3 parts .of epichlorothose of phosphorous acid and of phosphonic and phos- I phinic acids are to be understood. The invention is particularly concerned, however, with the stabilising of thiophosphoric acid l2-isopropyl-4-methyl-pyrimidyl-(6)1- diethyl ester and phosphoric acid-l3-methyl-pyrazolyl- (5)1-diethyl ester. M

In particular, active ingredients for'pesticides .of all types as pure substances, as technical crude substances, as ready-for-use preparationsor as solid, semi-solid or liquid concentrates for the production of the latter are meant by phosphoric acid esters to be stabilised. In

addition they can also be, for example, additives to lubricants and fuels, antistatic agents and flame-proofing a as xylene, benzene, diesel oil, kerosene, spindle oil or a petrolatum product, and 2-30% (calculated on the weight h dr n: .in t adlvi 3 par s "9f. Y sizc ns sat Product is-stored mh ane c u i enw I Y i YQ EJEampIe'3 jan alkyd. phenol-ethylene" ""oiiid'e" condeils (condensation product of 1 mol of nonyl-,'octy1- or isooetyl-phenolwith 5-10 mols of ethylene oxide) and parts of'xylene is stored for 130 days at At the end of this time, the content of phosphoric acid-[3- methyl-pyrazolyl-(S)l-diethyl ester has'sunk to 10 parts.

' An analogous composition in which 1 part of xylene ester which can be stabilised according to the present 7 of said ester) of one of the above mentioned stabilising a agents.

The stabilising effect of additives to phosphoric acid esters and compositions according to'the present invention is illustrated in the following examples. Parts are always given as parts by weight and the temperatures are in degrees Centigrade.

Example 1 An emulsifiable solution for the preparation of insecticidal emulsions consisting of I V 20 parts of thiophosphoric -acid-.l2 isopropyl-4 rnethylpyrirnidyl-(6)l-diethyl'ester- 35 parts, of an alkylphenol-ethylene oxide condensation has been replaced by 1 part of epichlorohydrin, remains unchanged after storing under the same conditions.

' Example 4 V a 7 Another emulsifiable solution of a phosphoric acid invention is obtained by dissolving 20 parts of phosphoric acid-[3-methyl-pyrazoly1-(S)l-diethyi ester, 8 parts of an d parts of an alkyl phenol ethylene oxide condensation Y product(condensation product of 1 mol of nonyl-, octylor iso-octyl phenol with 5-10 mols'of ethylene oxide), I I

and 4 parts of propylene oxide.

7 Example 6 The solution of Example 5 can also be stabilised if I 4 parts of cyclohexene oxide are usedinstead of 4 parts product (condensation product of 1 molvof nonylof propylene oxide.

Example 7 r emulsified stabilised solutionaccording to the V uti omhaving i a high concentration present invention which canibe used forthe preparation of an insecticidal emulsion is obtained by dissolving I 40 parts of thiophosphoric acid-[2-isopropyl-4-methylpyrimid yl- (6 )']-diethyl es ter, 2 y,pa-rts ot an -alkyl phenol-ethylene oxide condensation product (condensation product of 1 mol of nonyl-, octylor iso-octyl-phenol with -10 mols of ethylene oxide) and 12 parts of styrol oxide in 28 parts of xylene.

I Example '8 Another emulsifiable stabilised solution according to the present invention isobtained by dissolving 25 parts of thiophosphoric acid[2#isopropyl 4 methyl-pyrimidyl- (6)1-diethyl ester, 1 0 parts 'of 'en alkyl' phenohethylene oxide condensation product (condensation product of 1 mol of nonyl-,roctyl-, or is ooctyl-p henol with 5-10 mols of ethylene oxide) and 0.5 part "of cyclohexene oxide in 64.5 parts of benzene. r

A solution which can be-used as an insecticidal spray and which consists of 436 parts of thiophosphoricacidof epichlorohydrin, cyclohexene oxide, propylene oxide hydrin.

[2-isopropyl-4-methyl-pyrimidyl-( 6)J-diethyI ester and v 564 parts of kerosene is stored for 26 daysat 15. At the end of this time the content of the saidester, has sunk to 365 parts.

Under the same storing conditions, an analogously composed solution in which-'25 parts of kerosene have been replaced by '25 parts of epichlorohydrin, remains stable, i.e. there is no loss of content of the thiophosphoric acid ester namedf What I claim is: g y

1. The process for the stabilising of aphosphoric acid dialkyl ester selected from the group consisting of thiophosphoric acid-[Z-isopropyl 4 methyl-pyrimidyl-(6) 1- diethyl ester and phosphoric acid-[3-methyl-pyrazoly1- (5)]-diethyl ester, which comprises adding to'sa'id ester from 2% to 30%, calculated ,on the weight of said ester, of a stabilising agent-selected from th e grou consisting 4. The composition of matter comprising a phosphoric acid dialkyl ester selected from the group consisting of thiophospho'ric acid-[2i'sopropyl 4 methyl pyrimidyl- (6)]-diethyl ester and phosphoric a'cid-[3-methyl-pyrazolyl-(S)]-diethyl ester,' and from 2% to calculated on the weight of said esters, of a stabilising agent selected from the group consisting of epichlorohydrin, cyclohexene oxide, propylene oxide and styrol oxide.

5. The composition of matter comprising thiophosphori'c acid-[2-isopropyl-4methyl-pyrimidyl-( 6) 1 -diethyl ester, and from 2% to 30%, calculated on the, weight of said ester, of .the stabilising :agent epichlorohydrin.

6, The composition of matter comprising phosphoric 'acid-[3-methyl pyrazolyl-(5)l-diethyl ester,- and from 2 %'to 30%,.calculated onthe weight of the said ester,

: of the stabilising agent epichlorohydrin.

CuIyenor: lour'. Chem. Soc. (London), 1949, pp. 275-282,

Hazen et al.: Soap and SanitaryChemicals, vol. 22: 8,

' p. 151,153 and ,155 (1946) 

1. THE PROCESS FOR THE STABILISING OF A PHOSPHORIC ACID DIALKYL ESTER SELECTED FROM THE GROUP CONSISTING OF THIOPHOSPHORIC ACID-(2-ISOPROPYL - 4 - METHYLE-PYRIMIDLY-(6))DIETHYL ESTER AND PHOSPHORIC ACID-(3-METHYL-PYRAZOLYL(5))-DIETHYL ESTER, WHICH COMPRISES ADDING TO SAID ESTER FROM 2% TO 30%, CALCULATED ON THE WEIGHT OF SAID ESTER, OF A STABILISING AGENT SELECTED FROM THE GROUP CONSISTING OF EPICHLOROHYDRIN, CYCLOHEXENE OXIDE, PROPYLENE OXIDE AND STYROL OXIDE. 